Electric track-switch.



PATENTED JAN: 21, 1908.

R. A. BALDWIN. ELECTRIC TRACK SWITCH.

APPLICATION FILED DEC. 5; 1906.

' citizen of the Um'ted States, residing at ,to' be positioned by theswitchpoint which has UNITED-STATES} PA mi ROLLIN A. BALDWIN, OF NEWHAVEN CONNECTICUT, ASSIGNOR TO BALDWIN & ROWLAND SWITCH & SIGNAL CO, ACORPORATION OF CONNECTICUT. I

ELECTRIC rnAcx-s'wrrcn.

Specification of Letters Patent. Application filed December 5.190s.Serial No. 346.361.

Patented Jan. 21, 1 908 To all whom it may concern:

Be it known-that I, RoLLIN A. BALDWIN, a New Haven, in the county of NewHaven and State of Connecticut, have invented certain new' anduseful'Improvements in Electric Track-Switches, of which the followingis a full, clear, andexact description.

My invention relates to electrical track switches, particularly of thatcharacter used .in .street railway installations where. the switchpoints at the turn-outs are required motorman of ,each car before itenters the switch.

The principal object ofthe invention is to provide an electricallyoperated switch h'ch is actuated in the most positive man* her bythecurrent from the ordinary power circuit or trolley, in bothdirectionsof its throw. In other words, I aim to provide a separate electricalpower means for moving it in the two directions of its movement, so thatsprings, weights, alternative mechanical movements, and all similardevices are absolutely avoided. A further objec of the invention is toprovide an electrical switch which is positively set in one position orthe other wholly by the manipulations of the usual motor controller onthe car, and in which certain manipu'la.- tions always result, in acertain predetermined throw of the switch point, so that in the night,in the severest fogs or storms, and under all circumstances, themotorman is able to position the switch pointin advance of his car in acertain definite way, whether he is able to see it or not, and withoutthe necessity of looking at it in any case.

in a switch point. In other words, the H1001}? anism is designed topresent sufficient resistance to accidental displacement of the Wltchpoint to preclude its derangement by teams,

etc. -With these. and other objects in vicw It is also evident that bythis means the motor the invention consists in the features ofconstruction and combination hereinafter set.

forth and claimed. 4

In the drawings:. Figure 1 is aperspective view showing an automatictrack switch embodying the' principles of my invention; Fig. 2 is adiagrammatic view showing the electrical circuits thereof. 1

The ordinary track switch of a street railway is exposed to "the mostunfavorable infiuences possible. It is buried in the ground where it Isex osed to constant dampness and corroding iniihence, which is injuriousto all the metallic parts, and particularly injurious to any electricalswitches or connections.

The switch is also exposed to very hard usage by reason of the blows andimpacts it receives fromcars and teams, and above all, by reason of theobstacles and i111 ediments, such as mud, stones and dirt whicfi fall inthe path of the switch point, and cause the actuating,

devices to be overloaded to the breakin point. Finally, the mechanism iscalls upon to act at all sorts of varying electrical potentials,depending on the condition of the power circuit. In some cases thevoltage of the power circuit of a street railway falls very low, and thedevice must be able to work at such low voltage. Therefore, it must notbe injured by a resu'm tion of high voltage conclitions. Finally, t 0switch is not under the ins ection or supervision of ersons qualified toeep it in good order.- T e ordinary railroademployees are unfamiliarwith delicate mechanism, and are incapable of'making fine On all theseac- 1 counts it-is evident that, an automatic track switch to besuccessful must be constructed adjustments or repairs.

in the most simple and substantial way, so that it is )racticallyimpossible for'it to get out of or er under any'circumstances. Incarrying out myinvention I aim. to secure this result.

Referrin to the drawings in which like parts are sign, 1 indicates aportion of a'track rail con- 'taining a switch oint 2, pivoted at 3, soas to. swing back and orth in the rail 1 through alimited,arcofhmovelnent. 4 f4 denots an extension of the switch pointwlii c h ief'preferably integral therewith or rigidly attached thereto.This extension 4 con Lstitutes the part on which the devices'embodyingmy invention operat 1'.

designated by the same reference is received at its lower end in abearing 9, in-

tegral witlflthe .box} 5, and at its upper end passes through" astuliing box in the shelf or ledge "2', so as to be perfectlywater-tight at the point of its emergence from the box.- Byrtl'nsarrangement the shaft 8 is capable of transmitting an angular movementfrom the interior to the exterior of the box:

The shaft 8 has two crank arms 11 and 12, of which 11 isja short arm onthe outside of the box, while 12 is a considerably longer a'rin n the inide of the box, and preferably exten ding in tire same general directionas the crank arm 11. The crank arm 11 is connected by a link 13 with theextension 4 of the switch point. The crank arm 12 has a pitmanconnection 1 ith certain power devicds, by which the motion of theswitch point secured/7 The power devices wliich'operatc the pitman lflconstitute a very important feature of myinvention. in tlie preferredform make use of a cylindrical com artinent or casing.15;having acylinder hes. 16 bolted thereto so as, to be-ab olutely water tiight. Within this casing are contained a pairof magnet cdil's or solenoids 1.7,1 18, of which 17 is Wound Withfine wire, say No. 21, double cotton00V? cred, while 18 is wound with comparatively coarse "wire,forexarhple, No. 9 gage coils or solenoids are' cdexielly ositioned asrticularly sho n in Fig. 2, and are suitably separated by an insulatingpartition 19, of anysuitable sort. The tinan 14 extends in the directionofthe holl d vt interior of these coils .or solenoids, and has at itsinner end an iron core 20, which is ofsuflicient length and inodete anyangular mo velnp diameter to cooperate efficiently With, the twosolenoids and to-be sucked into one or the other of them, eccordingtowhich one is ener izcd. in Fig. 2 the core 20 is shown within thesolenoid 17, andis in a position to be drawn intothe solenoid, 18 incase the latterwere the one energized. :In the practical construction imount the solenoids i7, 18, on

a tube 21, so as to form it guide for the core or plunger 20. The coreor plunger 20 1s suii iclently loose n'the guide 51 to accomarn'idil towhich the pitrnan 18 connected. 1

"also fill the entire. cylinder or compartment with-transformer oil soas toitho'roughly insulate the-windings and exclude moisture.

The electrical connections will be clearly understood from aconsideration cl Fig. 2-.

ZQJQlXIQOY/GS a trollevcircuit closer of any late-d t the coil orsolenoid 17 is first energized by it These nt of the crank convenientform adapted to make connection with the power wire when a car passes.For the purposes of illustration I have shown a pair of metallic strips:23, which are separateil from the trolley ,wiie 24, but which arefinthe path of the'trdlley wheel 25, so that the" strips are tern brarilycharged during the interval that tie-. trolley Wheel is passing by. v

l indicates a Wire'connecting one or both of these strips to thesolenoid 17 having the fine wire, and 1 indicates a ground connec tion,constituting the other terminal thereof.

The solenoid or coil .18 having the coarse wire is connected in acircuit between the wiresm and m s m is attached to the trolley wire 24and m leads to'a special trolley section 26, which may be formed by ametallic tube surrounding aiportion of the trolley wire but insuereirom.By the above arrangement shunt connection with the power circuit, when.a car passes from left to right in Fig; 2. The coarse wire coil orsolenoid 18 isthereafter energized by a series connection through thecar motors, provided the motorman is drawing current when his trolleypasses over the tube 26.

' The operat on is as follows: IWill sup 1,. pose a car tobe moving inthe direction of the arrow in Fig. 2, so that its trolley wheel is aboutto engage the metallic strips 23 of the initial circuit closer 22.-Under these circumstances, the switch point 2 may be in any position,either at the extremes of its throw, or at an intermediate location.This position depends on the destination of assed. iatever the positionof the switcf point it is automatically set in advance of the car in apre. determined. way by the initial energization of the coil or solenoid17. This occurs when the trolley wheel of the car engages the strips 23,thereby raising such strips'to potential, and causing a current to flowthrough thew'ire l, winding 17, wire I, to ground. In the illustrationtheswitch point is moved to the left under these circumstances. Thisaction occurs regardless of any control of the'motorman and whethercurrent is assing through the car motors or not. in t e meantime, themotormsn has made up his mind, which way he Wishes to go, and in case heWishes to go straight ahead, he proceeds without turning ofi' hiscontroller, so'that the car motors are taking current when the trolleywheel passes over the tube. 26; But the current for the motors urposelyI the trolley :the preceding car whichpcssedunless thev switch has beenaccidentally or disturbed since the car under these circumstances has topass ,its own momentum. Under these condi tions, there is no circuitcompleted through the Winding 18, so that the switch point is notdisturbed from its initial position to the left, whichvis alwaysinitially. taken under the influence of the Winding .17, as abovepointed out. Thus, under these circumstances, the car is switched tomake the'turn.

. By reason of the initial movement-of the switch point 'as abovedescribed it is evident that the motorman is relieved of all necessityof looking at the switch point before his car reaches it. It'is merelynecessary for him to make certain manipulations of his controller to gostraight ahead, or to make a turn, as desired, and in practice thesemanipulations soon become a matter of habit, so that his mind is notdistracted from its regular duties in running the car. In stormy orfoggy weather, or dark ni hts, the procedure is exactly the same, anno.trouble is caused by the motorman not being able to see the switchpoint before he arrives at it.

It will be observed that the apparatus is completely water-proof in'use, and has no electrical contacts or parts liable to become corrodedor inoperative in use. The circuit Wires l, m and 'm are led into theapparatus through an ordinary conduit pipe 27, which is made water roofin the usual way, and leads to any ordinary outlet box near-a trolleyole or at any other convenient point. V6hatIclaim,is:- I 1. In anelectrical track switch, a box or casing having a cover bywhich it ishermetically closed, one end of said box or casing being depressed toform a ledge or shelf, a shaft having a bearing in the-bottom of the boxand rojectin upwardly through said ledge or s elf and aving a stuffingbox enagement therewith, a pair of cranks on said shaft one exterior andone interior of the box, and means inclosed within the box and acting onthe latter crank, and a link connection from the exterior crank to theswitch point to 'move'the switch point.

2. In an electrical track switch, a box or casing having a depressedfront portion, a crank projecting upwardly-through said portion andhaving a short crank arm outside the casing, connections from said crankarm to the switch, oint, a long crank arm on said shaft within t ecasing, a bearing on the bottom of the casing for said shaft, a pair ofsolenoids within'the casing, a single watertight compartmenttherefor,=and a pitman connection having a core extending into saidsolenoids but exterior to said water-tight compartment and pivoted tothe long crank arm.

3. In an electrical track switch, a box or casing having a'cover bywhich it is hermetically closed, a stuffing box in said casing, a

shaft projecting through said stufiing box, a

pair of solenoids within the casing, a guide within said solenoids, acylindersurrounding the solenoids and forming in conjunction with saidguide a water-tight compartment therefor, a coreor plunger within saidguide and connected to move said shaft, and insulating oil within saidcompartment whereby the windings of the solenoids are wholly inclosedand immersed in insulating oil. I

In witness whereof, I subscribe my signature, in the presence of twowitnesses.

BOLLIN A. BALDWIN.

Witnesses: i I

E. L. Bownns, WALDO M.--OHArIN.

